Band-forming strapping machine



Feb. 28, 1961 M. N. RIPLEY BAND-FORMING STRAPPING MACHINE 4 Sheets-Sheet 1 Filed April 11, 1958 FIG.

MILLS N. RIPLEY INVENTOR BLAIR 0nd SPENCER ATTORNEYS Feb. 28, 1961 M. N. RIPLEY BAND-FORMING STRAPPING MACHINE 4 Sheets-Sheet 2 Filed April 11, 1958 Yn'l'l'lll'n'" MILLS N. RIPLEY INVENTOR BLAIR 0nd SPENCER ATTORNEYS Feb. 28, 1961 M. N. RIPLEY 2,972,844

BAND-FORMING STRAPPING MACHINE Filed April 11, 1958 4 Sheets-Sheet 5 FIG. 3

MILLS N. RIPLEY INVENTOR BLAIR and SPENCER ATTORNEYS Feb. 28, 1961 M. N. RIPLEY BAND-FORMING STRAPPING MACHINE Filed April 11, 1958 4 Sheets-Sheet 4 FIG. 4

32 MILLS N. RIPLEY \NVENTOR BLAIR and SPENCER ATTORN EYS BAND-FORMENG STRAPPING MACHINE Miils N. Ripley, Scarsdale, N.Y., assignor to General Strapping Corporation, New York, N.Y.

Filed Apr. 11, 1958, Ser- No. 727,830

12 Claims. (Cl. 53-198) This invention relates to an improved band strapping machine capable of securing boxes and like packages of different cross-sectional configurations with metallic bands. More particularly, it relates to a machine which binds the packages with so called formed band, the band being supplied as flat stock and formed by the machine prior to or during the binding operation. The machine is thus adapted to utilize the less expensive fiat band stock while banding packages with the more desirable formed band; further efficiency of operation is derived from a minimum of handling of the hard-tomanage formed stock prior to the banding operation.

My invention is particularly adapted for use with strapping machines of the general type disclosed in the copending application for Automatic Package Banding or Strapping Machine, Serial No. 171,522, filed June 30, 1950, which has issued as US. Patent No. 2,864,303, dated December 16, 1958. In these machines the package to be bound is encompassed by a rotating, wrapping ring which, as it rotates about the package, pays out band under tension, the free end of the band being held by a gripper adjacent the package. A convolution of band is thus placed on the package for each rotation of the wrapping ring. These machines are adapted to ap ply either fiat or formed band.

Flat band, having a rectangular cross section, is prone to catch on clothing of those who come in contact with it Banded packages are often slid over floors of warehouses, railroad cars, etc. and fiat band tends to snagon projections such as nails or gouge into the floors themselves. Sliding movement is thus often rendered difficult, to say nothing of the resulting damage. Formed band, on the other hand, may be made with rounded edges which do not catch on protruding objects and packages so Wrapped are thus more easily handled and slide o er fairly irregular surfaces without damaging them. However, formed band is. considerably more expensive than fiat band and is quite dificult to handle because of its marked tendency to crimp. Sincethe edges are rounded, the band has at least one and often several longitudinal ribs or corrugations and when bent around a small radius they tend to crimp, thereby creasing the band in such bent configuration. Such creases are not readily removed and, consequently, this problem is a serious drawback to the use of formed band in high'speed automatic machinery It has'been proposed to situate a conventional band forming mill close by a band machine with flat band stock passing through the forming mill and then directly to the banding machine to be Wrapped around apackag'e. However, band forming mills are very expensive as regards both initial cost and operating expense. Also they take up valuable floor space, and require a large amount of operator supervision. of band utilized by these band strapping machines, the use of such a system results. in unduly high unit cost for formed band. Moreover, the Strapping machine itself often passesthe, band around Patented Feb. 28, 1961 rolls and tensioning rolls before paying it out to the wrapped package and, therefore, there remains the problem of creasing during the strapping operation.

Accordingly, it is an object of my invention to provide an improved'band strapping machine adapted to apply formed bands of various cross-sectional configurations. Another object of my invention is to provide a machine of the above character adapted to utilize a supply of relatively inexpensive'fiat band stock. A further object of my invention is to provide a machine of the above character requiring minimum handling of formed band. A still further object of my invention is to provide a machine of the above character capable of producing formed band from flat stock. Yet another object of my invention is to provide a band forming unit adapted for operation in a machine of the above character. Still another object of my invention is to provide a band forming unit which is inexpensive and simple in construction and may be readily attached to a strapping machine of the above Co seq ently fo h n y 1 ma y objec s u as. aside .1.

character without extensive alteration of the machine.

' Yet a further object of my invention is to provide a band forming unit of the above character which may readily be adapted to form band into a variety of configurations. Another object of my invention is to provide a band forming unit of the above character requiring a minimum of operator control and adjustment. Another object of my invention is to provide an improved formed band configuration obtainable from a band-forming unit of the above character. Other objects of my invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the features of construction, combinations of elements, and arrangementsof parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which: i a

Figure 1 is a simplified front elevation, partly broken away, of an improved band strapping machine incorporating the features of my invention and depicting the machine at the beginning of the Wrapping cycle.

Figure 2 is a fragmentary enlarged elevation of a part of the structure shown in Figure 1, showing in greater detail the relationship of the band-forming unit to the other parts of the machine, and showing the machine near the end of the wrapping cycle,

Figure 3 is a fragmentary plan view of the band-forming unit with its supporting structure in section, the parts being shown as seen when looking from the interior of the supporting frame shown'in Figure 1,

Figure 4 is a vertical section taken along the line 44 of Figure 3,

Figure 5 is a perspective view of a portion of band formed by the particular band-forming unit illustrated in Figures 3 and 4,

Figure 6 is a fragmentary section of a box secured with the band shown in Figure 5, and

Figure 7 is a perspective view of a portion of another band having a configuration obtainable from a bandforrning unit made according to my invention.

Referring first to Figure 1, a strapping machine of the type which may be used with my invention rests on pedestals it) and has a supporting frame generally indicated at 12 to which is secured a Wrapping unit generally indicated at 14. A band feed control unit generally indicated at 16 is disposed below unit 14 and a table 18 illustratively carries a ho); Zl) being bound within the. open central portion of the wrapping-unit 14, Wrapping unit 14 comprises a wrapping ring generally indicated at 22 supported for rotation on a series of rollers 24 and rotated thereon by a pinion 26 meshing with teeth 27 on the ring. Pinion 26 is connected to a motor by suitable mechanism (not shown). More particularly, as seen in Figures 1, 2, 3 and 4, ring 22 has a central web portion 23, an inner flange 3d and outer shoulders 32 (Figures 2, 3 and 4). The teeth 27 are formed on the outer portion of web 28 and extend beyond shoulders 32 to mesh with pinion 26 (Figure 1). Each of the rollers 24 has annular portions (not shown in detail) engaging shoulders 32 to support ring 22 and a central groove (not shown) providing way for the teeth. The rollers are journalled for'rotation on shafts 35 (Figure l) suitably aflixed to frame 12. Thus pinion 26 drives ring 22 for rotation on rollers 24 about table 1?; and box 20.

Ring 22 carries for rotation therewith a series of band guides generally indicated at 36 (Figures 1 and 2) for storing band fed to the wrapping unit 14 and a bandforming unit generally indicated at 38, to be described, which pays out band from the wrapping ring 22 to the box 26 during the wrapping or banding operation. cover it? (Figure 1) may be secured to frame 12 over the exposed portions of the wrapping unit.

Still referring to Figure 1, band 42 issuing from hand feed control unit 16 passes over idiers 44 and 46 and thence onto wrapping ring 22 within guides 36. From the guides band 42 passes through the band-forming unit 38 (Figure l) and, during operation, to gripping, tensioning, cutting and welding apparatus beneath table 13. More particularly, as seen in Figure 2, the apparatus beneath table 18 includes a tensioning gripper 48, a first holding gripper 50, a second holding gripper 52, a cutter-crimpcr 54 and welding electrodes 56 and 58. These parts and a detent 66 mounted on an arm 62 are controlled by mechanism (not shown) more fully disclosed in the copending application Serial No. 171,522. They operate in conjunction with wrapping ring 22 in a manner presently to be described.

At the beginning of the wrapping cycle the band 42 is held near its free end 42a by tensioning gripper 43. Ring 22 is made to revolve by pinion 26 in the direction of the arrow (Figure 1). The band, extending from band-forming unit 38, is thereby wrapped around box 2% during this operation it is pulled from ring 22 through unit 3% as required. After a complete revolution of ring 22 a single turn of the band is placed around box 26 and the machine is then disposed as shown in Figure 2, with band 42 passing around detent 66. At this point, in rapid sequence, gripper d grips the band and tensioning gripper 43 moves to the left as seen in Figure 2 to tighten the band around the'box. Gripper 52 then grasps the tightened band near the free end 42a and gripper 48 releases the band to pick up the other portion 42!) running to unit 38. Cutter-crimper 54 then moves upwardly to cut and crimp the baud. Finally welding electrodes 56 and 58 move upwardly to weld the end E20 thus formed to free end 42a. The banding operation is now complete and box 20 may be removed by movement toward the front of the machine or toward the reader. After a new box has been properly positioned, the Wrapping cycle is again initiated in the above described manner.

According to my invention, band-forming unit 3% is adapted to form the band 42 in the strapping machine itself, e.g. from flat strip into the shape shown in Figure 5. This unit comprises a pair of interfitting forming rolls to form the band and a suitably braked idler roll to provide desired tension, thereby to accept and form the band in a manner to be described. The unit occupies the position of tensioning rollers formerly attached to wrapping ring 22. I have found that the tension required to efliciently bind or wrap the box is ideal-for drawing the hand through forming rolls of the type to be described and, therefore, the band-forming unit, in addition to forming the band, functions also as a tensioning device. Moreover, by positioning the forming unit as thus described, I form the band just prior to the strapping operation and the handling of formed band is thereby reduced to a minimum. As will be seen, the band-forming unit 38 is simple in construction and can easily be installed in a conventional strapping machine such as the one described above.

Turning now to Figures 3 and 4, band-forming unit 38 has a mounting plate 64 afixed to web 28 of ring 22 by screws 63 and 65. Plate 64 carries an inner end plate 71 suitably secured thereto. Shafts 66, 68 and 70 are secured at their inner ends in plate 71 and at their outer ends in an outer end plate 72. Shaft 66 carries for rotation thereon a tensioning roller 74. A pair of forming rolls generally indicated at 76 and 78 are rotatably mounted on shafts 68 and 70. In a manner to be described flat stock fed between rolls 76 and 78 may be formed into a desirable cross sectional configuration and roller 74 may be adjusted to provide optimum tensioning of the band for the wrapping operation.

More particularly, shafts 66, 68 and 70 are preferably rigidly secured to plates 71 and 72 by set screws 84, 86, 88, 9t), 92 and 94. Tensioning roller 74 is formed with an annular band guide 74a and a brake drum 74b. It is properly positioned for rotation on shaft 66 by a boss portion 740 and a flange portion 74d. A U-shaped brake shoe 96 (Figure 4) fitting over drum 74b has leg portions 96a and 26b connected by an adjusting bolt 98. Thus a nut 160 may be turned inwardly or outwardly on bolt 93 and against leg portion 26a to adjust the frictional force with which brake 96 grips the drum. A pin 162 suitably secured in plate 64 extends between leg portions 96a and 96b to restrain brake 96 from rotation during rotation of roller 74. Consequently the brake inhibits rotation of roller 74 caused by the movement of the band 42 (Figure 4) over guide 74a thereof. The tension thereby exerted on the band by roller 74 is thus readily and accurately adjustable by suitable manipulation of nut 100.

As best seen in Figure 3, a bushing 104, secured to shaft 68 by a set screw 106 serves as a bearing for forming roll 76 rotatably mounted thereon, while flange portion 19 1a thereof maintains roll 76 substantially adjacent plate 64. Bushing 104 is preferably made of a suitable sintered metal capable of holding a supply of oil for the forming roll which rotates thereon. It will be noted that forming roll 76 and bushing 164 are secured on an eccentric portion 68a of shaft 68. Accordingly, upon loosening set screws 88 and and rotation of eccentric portion 68a with shaft 68 in plates 64 and 72, roll 76 may be moved toward or away from the co-operating roll 78. The clear-- ance between rolls 76 and 78 may thus be readily adjusted as desired. A bushing 198 similar to bushing 106 is secured to shaft 70 by a set screw 110. Bushing 108 provides a bearing surface for rotation of forming roll 78 and a flange portion 108a maintains the roll substantially adjacent inner end plate 71. As thus mounted for rotation on shafts 68 and 70, forming rolls 76 and 78 are adapted to form a flat band passing therebetween into a desirable shape, preferably one with rounded edges as mentioned above or beveled edges to be described.

More particularly, roll 76 has a pair of convexly cross-sectional annular ridges 112 and 114 joined by an annular groove 116. Roll 78 has concave annular grooves 118 and 120 interfitting with ridges 112 and 114 and an annular ridge 122 fitting within groove 116. Band passing through the forming rolls fits between and is guided by outer ridges 124 and 126 on roll 78 interfitting with annular depressions 128 and 130 on roll 76. A length of band formed by rolls 76 and v78 is illustrated in Figure 5. It has longitudinal, rounded ribs or corrugations 132 and 134 formed by ridges 112 and 114 and 'grooves 118 and 120 respectively. Ribs 132 and 134 are joined by a flat web 136 formed between ridge 1'22 and groove 116.

Referring to Figure 1, band 42 coming from hand feed control unit 16 and idlers 44 and 46 (Figure 1) enters upon wrapping ring 22. As best seen in Figure 4, the hand then traverses the forming unit 38 by passing first over guide 74a of tensioning roller 74 and then between forming rolls 76 and 78, the end thereof being fastened under table 18 by the tensioning gripper 48 (Figure 2). Consequently, as wrapping ring 22 revolves in the direction of the arrow of Figure l in the manner described, it draws band from the forming unit 38 revolving therewith. The flat band in the guides 36. is thereby drawn through the band-forming unit and, in passing between forming rolls 76 and 87 (Figure 4), it acquires a crosssectional shape as illustrated, in Figure 5 in the manner previously described, after which; it is wrapped around the box 20. As seen in Figure 6, the edges ofa band having such shape naturally are flush with the surface of the box, so there is small chance of catching anything therebetween when the box is moved about after strapping. Moreover, the ribs 132 and 134 provide rounded sliding surfaces to facilitate movement of box 20 over floors, etc., without damaging them.

It should be understood, however, that this invention is not limited to the particular shape of band shown in Figure 5. A different shape can be produced merely by altering the peripheral shape of rolls 76 and 78. For example, another desirable band configuration obtainable from my band-forming unit is illustrated in Figure 7. As shown therein, the band may have a centrally disposed flat web 138 with flat beveled portions 140 and 142 angularly formed along the edges thereof. I have found this shape to be particularly well adapted for the strapping of packages of brick.

It will also be seen that the machine forms the band immediately prior to wrapping it around the package or box. The difficult handling of formed band is thereby reduced to an absolute minimum. In fact the only part to engage the formed band prior to banding is the detent 60 which, as explained above, touches the band at one point thereof during a short part of the wrapping cycle. Naturally the radius of detent 60 is made large enough to prevent dimpling of the ribs 132 and 134 when the band is bent therearound. The band-forming unit 38 thus eliminates the need for the purchase of preformed band or the use of a separate band forming mill with the attendant disadvantages enumerated above. Finally, forming unit 38 is, as is readily seen, a relatively simple device easily incorporated in existing machines. Forming rolls may be included in the forming unit to impart practically any desired cross sectional configuration and roll change may be elfected with ease. Unit 38 requires negligible operator control adjustment; however, when adjustment is desired, the unit is readily accessible for setting of both the brake tension via nut 100 and the forming roll cleari ance by adjustment of eccentric shaft 68.

It will thus be seen that the objectsset forth above, among those made apparent from'the precedingdecription, are efficiently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

I claim:

1. In an improved package banding machine adapted to bind a package with formed metallic band of a given cross-sectional configuration, and having a wrapping ring adapted to draw band from a supply thereof, said supply being fixed with respect to the path of movement of said wrapping ring, means for gripping the free end ofsaid band adjacent said package, means for rotating said ring whereby band is drawn therefrom and wrapped around said package, means for fastening the band so wrapped and severing it from the remainder thereof, the improve-. ment comprising band forming rolls attached to said wrapping ringand adapted to impart said cross-sectional configuration to flat band passing therebetween, whereby band from such fixed supply may be threaded through said forming rolls to be formed with said configuration immediately prior to being wrapped around said package.

2. The combination defined in claim 1 including a brake adapted to restrain the movement of band to said box during the wrapping operation.

3. In an improved package banding'rnachine adapted to bind a package with formed metallic band of a given cross-sectional configuration, and having a wrapping ring adapted to draw fiat band from a stock thereof, means for gripping the free end of said band adjacent said package, means for rotating said wrapping ring whereby band is drawn therefrom and wrapped around said package, the improvement comprising a band-forming unit secured to said wrapping ring to travel therewith and adapted to form said band as it leaves said ring to be wrapped around said package, said band-forming unit comprising co-operating forming rolls adapted to form band passing therebetween into said given configuration, a brake adapted to tension band passing through said forming rolls, said brake being disposed to act on said band before it passes between said forming rolls, and means for adjusting the restraining force of said brake, thereby to regulate the tension of said band as it is wrapped around said package.

4. The combination defined in claim 3 including means for adjusting the clearance between said forming rolls.

5. In a band-forming unit adapted to form metallic band issuing from the wrapping ring of a package banding machine, the combination of co-operating forming rolls adapted to form band passing therebetween, a brake adapted to tension band passing between said forming rolls and means for adjusting the restraining forces of said brake thereby to regulate the tension on said band.

6. The combination defined in claim 5 including means for mounting said unit on said wrapping ring to rotate therewith.

7. In a band-forming unit adapted to form metallic band issuing from a wrapping ring of a package banding machine, the combination of means for securing said unit to said wrapping ring for rotation therewith, cooperating forming rolls adapted to form band passing therebetween, and a tensioning roller adapted to tension band passing between said forming rolls, said tensioning roller having formed thereon a brake drum and a band guide adapted to guide band over said roller prior to passage between said forming rolls, a brake adapted to engage the surface of said brake drum and thereby brake rotation of said tensioning roller and movement of said band passing through said band guide, and means for adjusting the pressure of said brake on said brake drum to regulate the tension of said band issuing from said forming rolls.

8. The combination defined in claim 7 including a generally U-shaped brake fitted over said brake drum to exert a friction force thereon, means preventing rotation of said brake with said brake drum, and adjustable means for drawing together the arms of said U, to vary said friction force, thereby to regulate the tension of said band issuing from said wrapping ring.

9. In a band-forming unit adapted to form metallic bandissuingfrom a wrapping ring of a package banding machine, the combination of a mounting plate adapted to be secured to said wrapping ring to rotate there with, an end plate, a first shaft secured between said plates and carrying for rotation thereon a tensioning roller, said tensioning roller having a cylindrical band guide, a second shaft and a third shaft extending between said plates, said second shaft carrying a first forming roll and said third carrying a second forming roll, means rotatably mounting said forming rolls on said second and third shafts, said forming rolls co-opcrating with each other to form band passing therebetween, and means for varying the clearance of said forming rolls.

10. The combination defined in claim 9 in which said second shaft has an eccentric portion carrying said first forming roll and is releasably secured in said mounting plates, whereby said second shaft 'may be rotated to move said first forming roll toward and away from said second forming roll thereby to vary the clearance between said forming rolls. 3

11. The combination defined in claim 9 including bushings interposed between said forming rolls and said second and third shafts, said bushings providing surfaces for rotation of said rolls, said bushings having flange portions adapted to position said forming rolls in line with said band guide of said tensioning roller.

12. The combination defined in claim 9 including a brake drum on said tensioning roll, a brake adapted to engage said drum, means for adjusting the force exerted by said brake on said drum, thereby to vary the tension of band passing over said band guide and issuing from said forming rolls, and means adapted to prevent rotation of said brake with said brake drum.

References Cited in the file of this patent UNITED STATES PATENTS 1,221,089 Pierce Apr. 3, 1917 2,815,626 Fahrenbach Dec. 10, 1957 2,864,303 Brown Dec. 16, 1958 

